Non-Small Cell Lung Cancer - Diagnostic Tests

It should also be noted that about 98% of abnormalities seen on CT scans turn out to be benign. Even after rescreening, many scans will show suspicious areas that turn out to be harmless but will require invasive and expensive biopsies. Additional experience with CT scans, however, may allow experts to better determine which abnormalities are likely to be benign.

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High-risk individuals who are still interested in early screening with CT scans should ask their physician about available clinical trials.

Other Imaging Tests for Staging and Tracking Cancer

Computed tomography is the standard imaging procedure for determining if and where the cancer has spread (metastasized), for example to head, bone, or abdomen. Other imaging tests, however, may be useful for staging and tracking lung cancers.

Positron Emission Tomography. Positron emission tomography (PET), specifically a technique known as FDG/PET, is the most accurate noninvasive test for detecting early lung cancer. It is also the best imaging technique for staging lung cancers, not only those located in the lungs, but also those that have spread, particularly into the space between the two lungs (the mediastinum). With this imaging test, the patient is first injected with a specially formulated liquid sugar (called FDG), and then viewed with a machine that records energy given off by tumor cells.

PET is expensive and not widely available. However, its supporters suggest that it may prevent many unnecessary surgeries by identifying patients whose cancer has advanced past the stage at which surgery is helpful. There is some evidence that FDG/PET scan can detect a metabolic response to treatments that may help predict outlook.

Scintigraphy. Scintigraphy is an imaging procedure in which patients are administered low-level radioactive agents that bind to cancer cells, which then can be tracked by special cameras to reveal the cancer cells' location and intensity. Agents selected are those that can best bind successfully with specific tumor types. For example, a 2001 study of the binding agent 111In-DOTA-LAN demonstrated excellent results in identifying non-small cell lung tumors. (This study further suggests the possibility of using such highly-targeted binding agents as lung cancer treatments.)

Magnetic Resonance Imaging. Magnetic resonance imaging (MRI), an imaging procedure that uses radio wave energy, is frequently used instead of CT scanning to locate brain and bone metastases that can be associated with lung cancer.